All major updates come with issues and the Cyanogen OS 13 is no exception. The update bearing build version ZNH0EAS26M and based on Android Marshmallow version 6.0.1 was rolled out to OnePlus One users via the over-the-air mechanism earlier in April.

Soon after the rollout, users reported several bugs. Thankfully, fixes to some of the issues are now available, and credit should go to folks at the OnePlus forum, who have shared them. Check out the list below.

Battery drain with Wi-Fi: If you experience unexpected battery drain while on Wi-Fi after the update, go to Settings>> Location>> Options (the three dots at the top right corner)>> Scanning>> Disable Wi-Fi Scanning.

SIM card issue: If you have SIM card issues, just perform a reset of your network settings and check if that is helpful. To perform a reset go to System>> Backup and restore>> Reset network settings.

Trebuchet crashes: If the Trebuchet default launcher crashes, just go to Settings>> App>> Trebuchet and empty data and cache.

Google Play services draining battery: If the Google Play services is draining your battery, do the following steps to resolve the problem.

Boot the phone into recovery model, and wipe the cache partition (This process would take about 5-20 minutes)

After wiping the cache, reboot the phone and add your Google account

A member,who shared this fix on the forum, claims that his battery drain has dropped dramatically and his battery statistics show the correct figure.

Encryption issue: Many users on OnePlus forum have reported that updating an encrypted device to Cyanogen OS 13 does not work.

"I recently did an over the air update for my encrypted OPO to ZNH0EAS26M. After the phone restarted and went into the update mode, my phone requested my encryption pattern. Despite being correct, the pattern was rejected," states a user on CynogenMod jira site.

"This is a very serious problem as people installing what should be a safe upgrade are losing access to all of their data. While it is possible to use adb sideload to install the previous the previous version, it's a bit technical and beyond many people's abilities. Outside of flashing an old version, the only option is a full reset which means the user will lose all of their data," he added.

To resolve this problem you might consider installing the previous Cynogen OS version 12.1 via ADB sideload. Head over here for more help.

Contacts missing after update: If the message and contacts are missing after the update, go to Settings>> App>> Contacts>> Permissions. Now disable the permissions on the Contacts app. To apply the changes reboot the phone, once the process completes, go to the Contacts app. The app will now begin requesting permissions for it to work, so grant the permissions. You should now be able to see your contacts as usual.

We will update the list as more fixes become available. Until then, head over to the OnePlus forum to learn more about resolving your problems.